Improper Certificate Validation in RabbitMQ Java Client Library - CVE-2026-63336

 

Improper Certificate Validation in RabbitMQ Java Client Library - CVE-2026-63336

Published: July 9, 2026 / Updated: August 19, 2026


Vulnerability identifier: #VU137272
CSH Severity: Medium
CVSS v4: 9.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63336
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to intercept and modify transmitted data.

The vulnerability exists due to improper certificate validation in ConnectionFactory.useSslProtocol() and TrustEverythingTrustManager when establishing TLS connections without explicit trust configuration. A remote attacker can present a crafted certificate to perform a man-in-the-middle attack to intercept and modify transmitted data.

Hostname verification is disabled by default, which further facilitates exploitation.


Affected software

RabbitMQ Java Client Library
openEuler
rabbitmq-java-client
rabbitmq-java-client-doc
rabbitmq-java-client-javadoc

How to mitigate CVE-2026-63336

Install security update from vendor's website.

RabbitMQ Java Client Library - update to 5.33.0
rabbitmq-java-client - update to 3.6.5-4
rabbitmq-java-client-doc - update to 3.6.5-4
rabbitmq-java-client-javadoc - update to 3.6.5-4

External References

Related Security Bulletins